Milk Protein and Enzymes Symposium: Don't Have a Cow—Plant Proteins, Bovine Protein Expression, and Milk Humanization

Milk Protein and Enzymes Symposium: Don’t Have a Cow—Plant Proteins, Bovine Protein Expression, and Milk Humanization

306 The dairy matrix—Bioaccessibility of nutrients and physi- complete proteins because of their relatively high amount of EAA and ological effects. S. L. Turgeon*, STELA Dairy Research Centre and branched chain amino acids, whereas most singular plant proteins are Institute of Nutrition and Functional Foods (INAF), Department of not complete proteins. Therefore, combining multiple plant proteins is Food Science, Université Laval, Québec City, QC, Canada. necessary to get a complete protein. This presentation aims to discuss the key differences in the structure, functionality, and bioavailability of Studies have linked food structure and texture to kinetics of nutrient bovine versus plant proteins. delivery. Changes in some nutrient release rates, such as for protein and lipids, could induce different physiological effects (e.g., satiety effect, reduction of postprandial lipemia). Examples will be presented to 308 Sustainability of dairy product production on a protein showcase the contribution of dairy food structure, as found in yogurt and basis. Y. Wang*, Innovation Center for US Dairy, Rosemont, IL. cheese, on nutrient release rates. The impact of the casein:whey protein ratio or fiber addition on digestion kinetics of protein, and subsequently, Global agriculture faces the prospect of a changing climate and the satiety, was examined in one study. A static in vitro digestion model was challenge of feeding the fast-growing world’s population. It has been used on experimental yogurts differing in the casein-to-whey protein estimated that we need to produce more food in the next 40 years than ratio (C:W) or dietary fiber content. Healthy men (20) consumed the 5 we have ever produced in human history given the projected population isocaloric/isoproteinemic yogurt snacks previously studied. Ad libitum growth, the limited farmland and the competition with urbanization. food intake was monitored 2.5 h post-snack consumption. A human clini- Foods derived from plants and animals can both provide protein, but cal trial revealed that yogurt formulation with increased whey protein there are some differences nutritionally, environmentally and more. This content significantly reduced subsequent energy intake compared with paper will provide a life cycle perspective for dairy protein production the control, and increased satiety. This result was linked to a slower in to further engage dairy sustainability discussions. For years, US dairy vitro disintegration rate. Soluble protein release for yogurt increased in farmers have been using technology and advanced management practices whey protein whereas no difference was observed for yogurts with fiber. to increase efficiency and reduce environmental impact. The Innovation A second study allowed for the discrimination of the effects of cheese Center for US Dairy commissioned a series of life cycle assessment attributes on lipid release and absorption. Nine commercial cheeses studies (Thoma et al., 2010, https://data.nal.usda.gov/dataset/data- were digested in vitro and 2 were selected for an in vivo study. Healthy greenhouse-gas-emissions-milk-production-and-consumption-united- women/men (43) ingested 33 g of fat from cheddar, cream cheese or states-cradle-grave-life-cycle-assessment-circa-2008; Henderson et al., butter, incorporated in a standardized meal. Plasma concentrations of 2012, University of Michigan and University of Arkansas) to understand triglycerides (TG) were measured before the meal and at 2, 4, 6 and 8 the environmental impacts of dairy production, processing and trans- h. At the end of the in vitro gastric digestion, cheddar and cream cheese portation. For example, based on a 2010 study, the US dairy industry showed different disintegration, attributed to the texture and manufac- contributes only 2% of GHG, 5% of water withdrawal and 9% of US turing processes. The in vivo study revealed that cream cheese, but not cropland usage. Dairy cattle rely primarily on forages, crop residues, cheddar, induced a more important increase in TG concentrations than and agri-food industry by-products that are not edible for humans, to the butter (∆ vs baseline: +44% vs +24%, P = 0.002) at 2 h. These stud- produce a much more valuable food for humans. According to an FAO ies demonstrate that the dairy food matrix per se modulates nutritional study, 86% of the global livestock feed intake in dry matter consists properties. Studies published on this topic will be included to put into of feed materials that are not currently edible for humans (Mottet et perspective the role of the dairy food matrix on nutrient release, the al., 2017, Global Food Security 14:1–8). A similar study in the US physiological effects, and how this can be compared with other foods. [Tricarico, 2015, J. Dairy Sci. 98 (Suppl. 2):712] showed that 20% of dairy feed is human-edible by composition and only 0.9% of dairy feed Key Words: nutrient delivery, dairy food, food structure is in competition with humans by demand. Furthermore, replacement of edible feed crops with human-inedible biomass in animal diets is a potential strategy that could reduce food-feed competition and mitigate 307 Functionality, bioactivity, and structure of bovine and the environmental impacts of livestock (Salami et al., 2019, Anim. plant proteins. H. Patel*, US Dairy and Foods Consulting LLC, Feed Sci. Technol. 251:37–55). For dairy products and the ingredients Plymouth, MN. industry, it is important to understand the importance of environmental It is well known that the sequence of amino acids determines the stewardship. 3-dimensional structure of proteins, and that protein structure deter- mines its function. The amount of essential amino acids present in the protein determines protein quality. In the recent years, there has been 309 Humanization of bovine milk using modern genetic an emerging consumer trend toward plant-based foods and beverages, technologies. G. Laible*, AgResearch, Ruakura Research Centre, which is mainly driven by “vegan” and “flexitarian” lifestyles. It also Hamilton, New Zealand. offers more choice of food formats to consumers. Plant-based proteins The domestication of cattle has provided humans with almost unlimited differ significantly in their structure, functionality and bioavailability access to bovine milk and processed dairy products that are important compared with bovine proteins due to differences in their amino acid human foods.They provide an excellent source to meet human nutritional profile, the sequence of amino acids, the way they are folded to form demands for proteins, lipids, carbohydrates, and minerals.Although 3-dimensional structures and the amount of essential amino acids (EAA). regarded as a high-quality food source, cows’ milk has evolved to deliver The structure-function relationship of bovine proteins is well studied, optimized nutrition to the suckling calf and not as human food.Hence, whereas there is limited information available about plant proteins. there remains great potential to improve all major components of cows’ The bovine proteins, particularly whey proteins, are considered as milk to further enhance benefits for human health and wellbeing tailored

J. Dairy Sci. Vol. 102, Suppl. 1 267 to the different stages of life and their specific nutritional demands. 310 Taking a page out of nature: Catering to the future of Compared with human milk, cows’ milk has a higher protein content, proteins. B. Oommen*, Perfect Day Inc., Berkeley, CA. greater casein to whey protein ratio, lower lactose levels and more Global demand for high-quality animal-sourced protein is expected to saturated and less unsaturated fats. Efforts to change bovine milk by rise substantially over the next 2 decades as population grows and global conventional selective breeding approaches were largely unsuccessful. household incomes rise. Simultaneously, climate experts are calling for Technological progress for efficiently introducing targeted and precise a rapid transition away from animal-derived foods in an effort to curb genetic changes provides new opportunities to directly change specific greenhouse gas emissions from animal agriculture. Novel solutions characteristics of bovine milk. This includes humanizing bovine milk are needed for producing quality protein with minimal environmental for superior infant nutrition or altering bovine milk to accommodate the and climate impacts. Perfect Day has developed a means of producing different nutritional requirements of adolescents, adults, and elderlies. dairy protein—nutritionally and chemically the same as conventional Early proof-of-principle studies aimed at improving cows’ milk by bovine dairy protein—via the fermentation of bioengineered microflora. complementing it with additional antimicrobial human whey proteins This is the same technology widely employed by the food industry to used transgenic technology and were hampered by low acceptance. Since produce ingredients such as vitamins, amino acids, flavors, enzymes, then technology has become much more refined and it is now possible and rennet for cheese making. The first non-animal whey protein looks to humanize cows’ milk without leaving a technological footprint. If and behaves similar to its bovine counterpart. Similar processes could this new, so-called genome editing technology will be received with be used to produce a variety of other common food ingredients and greater levels of acceptance is still uncertain. Much will depend on our materials that are sourced from animals today. On a longer time scale, ability to develop proof of concept models. This is particularly important the same approach could be used to manufacture fully designed novel because milk is a very complex biological fluid and the changes resulting proteins that could be superior in nutrition and functionality than what from a specific component can potentially lead to more wide-ranging nature has provided thus far. implications. Only with appropriate animal models will we be able to fully evaluate potential risks and clearly demonstrate health benefits for consumers that could be delivered by these enhanced food products. Then it is up to the consumer to decide whether these new food products provide sufficient additional health benefits to outweigh any remaining technological risks.

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